JP2021185751A - Riding working machine - Google Patents

Abstract

To downsize a link mechanism for lifting up and down a working device while the lowest ground height of a working machine is kept high.SOLUTION: A riding working machine includes a portal rear axle case 11R having a lateral transmission case part 13 in a position higher than a shaft center of a rear wheel. There are provided in the rear part of a vehicle body frame 10, a lateral frame 10B for connecting the rear parts of a main frame 10A at a rear side from the lateral transmission case part 13, and a lower fulcrum bracket 15 extending downward from the main frame 10A in the rear side part of the lateral transmission case part 13. A top link mounting part 50 is provided above the lateral frame 10B, and a lower link mounting part 52 is provided in the lower end part of the lower fulcrum bracket 15. The lower link mounting part 52 is set in a height position equivalent to the lower edge of the lateral transmission case part 13.SELECTED DRAWING: Figure 6

Description

The present invention relates to a passenger work machine provided with a vehicle body frame supported by a front axle case and a rear axle case, and to which a link mechanism to which a work device is connected can be attached to the rear portion of the vehicle body frame.

As described above, in a passenger work machine provided with a vehicle body frame supported by a front axle case and a rear axle case, it is easy to construct a vehicle having a high ground clearance between the left and right wheels. That is, for example, when the work machine is configured with a monocoque car body without using a car body frame, the axle case is moved from the mission case provided at the center in the left-right direction of the car body toward the left and right lateral sides. It is extended and the rear wheel is supported at the lateral end of the axle case. With such a structure, the minimum ground clearance tends to be a low height such as the lower edge of the mission case, which is lower than the location of the axle. In comparison, if the front axle case and rear axle case are formed in a gate shape in the front-rear direction and a vehicle body frame is provided on top of this, the minimum ground clearance will be higher than the location of the axle, and ridges and crops will be produced. It is easy to obtain a passenger work machine that is convenient for straddling or working in deep paddy fields.
As such a passenger work machine, conventionally, the top link is supported by a member erected upward of the vehicle body frame at the rear of the vehicle body frame, and a lower member extends downward of the vehicle body frame. There is a structure in which a link is supported (see Patent Document 1).

Japanese Unexamined Patent Publication No. 9-275707 (see paragraph "0011" in the specification and "FIG. 4" and "FIG. 6" in the drawings).

According to the above prior art, at the rear of the vehicle body frame, an upward frame that stands up from the main frame and a downward frame that extends downward are provided, and a top link is attached to the upper end of the upward frame. The part is provided, and the lower link mounting part is provided on the downward frame.
With the structure configured in this way, a work machine with a high ground clearance can be obtained, but the swing fulcrum position of the top link and the swing fulcrum position of the lower link are the upper end of the upward frame. It is provided on the downward frame in the rear extension portion of the vehicle body frame.
As a result, the rocking fulcrum position of the top link and the rocking fulcrum position of the lower link exist at a position relatively high from the ground surface. When the work device is connected to the link mechanism centered on the swing fulcrum at such a high position to move up and down, the amount of forward and backward movement of the work device associated with the lift operation amount of the link mechanism should be reduced. In addition, it is necessary to increase the link length. For this reason, when constructing a work machine having a high ground clearance, the link length may become long, which may lead to an increase in the size of the entire work machine including the work equipment, and there is room for improvement in this respect.

The present invention is to provide a passenger work machine capable of downsizing a link mechanism for raising and lowering a work device while maintaining a high ground clearance of the work machine.

In the passenger working machine according to the present invention,
A front axle case with a power transmission mechanism that transmits power to a pair of left and right front wheels,
A rear axle case with a power transmission mechanism that transmits power to a pair of left and right rear wheels,
A vehicle body frame supported by the front axle case and the rear axle case is provided.
The engine and transmission case are supported by the body frame,
The vehicle body frame includes a pair of left and right main frames erected over the front axle case and the rear axle case.
The rear axle case connects the pair of left and right vertical transmission case portions that support the left and right rear wheels to the lower portion and the upper portions of the vertical transmission case portions at a position higher than the axis of the rear wheels. With a sideways transmission case, it is formed in a portal shape in the front-back direction.
A lateral frame connecting the rear portions of the main frame to the rear of the vehicle body frame on the rear side of the lateral transmission case portion, and a lateral frame extending downward from the main frame at a rear portion of the lateral transmission case portion. With a lower fulcrum bracket,
A top link mounting portion capable of connecting the top link is provided on the horizontal frame.
A lower link mounting portion to which a lower link can be connected is provided at the lower end of the lower fulcrum bracket.
The lower link mounting portion is characterized in that it is set at a height position comparable to that of the lower edge of the lateral transmission case portion.

According to this configuration, the rear axle case connects the pair of left and right vertical transmission case parts that support the left and right rear wheels to the lower part and the upper parts of the vertical transmission case part at a position higher than the axle center of the rear wheels. A vehicle body frame having a pair of left and right main frames is erected over the axle case and the front axle case after being formed in a gate shape in a front-rear direction with a lateral transmission case portion. As a result, the height of the lower edge of the lateral transmission case portion can be made higher than the axis of the rear wheel, and the minimum ground clearance of the vehicle body can be kept high.
A top link mounting part that can connect the top link is provided on the horizontal frame that connects the rear parts of the main frame, and the lower link can be connected to the lower end of the lower fulcrum bracket that extends downward from the main frame. A lower link mounting portion is provided, and the lower link mounting portion is set at a position as high as the lower edge of the lateral transmission case portion. As a result, the height position of the lower link mounting part is about the same as the lower edge of the lateral transmission case part corresponding to the minimum ground clearance while making the necessary height difference between the top link mounting part and the lower link mounting part. Is set to the height of. As a result, the height position of the lower link mounting portion is brought as close to the ground as possible while avoiding the lower ground clearance due to the presence of the lower link mounting portion. As a result, the inclination angle of the lower link having a predetermined length connecting the lower link mounting portion and the working device with respect to the horizontal plane becomes gentler.
As a result, it is possible to reduce the amount of forward / backward movement of the work device with respect to the amount of elevating operation of the lower link while adopting a relatively short lower link, and it is less likely that the entire work machine including the work device will be increased in size.

In the present invention, it is preferable that the lower fulcrum bracket is in contact with and connected to the rear surface of the lateral transmission case portion.

According to this configuration, the lower fulcrum bracket for providing the lower link mounting portion can be utilized as a connecting member to the rear surface of the lateral transmission case portion, and the connecting structure of the rear axle case to the vehicle body frame can be strengthened. ..

In the present invention, a lift arm for raising and lowering the lower link connected to the lower link mounting portion is provided.
A swing fulcrum axis along the left-right direction of the lift arm is pivotally supported by a pair of left and right support brackets.
It is preferable that the support bracket is detachably attached to the upper part of the lateral transmission case portion.

According to this configuration, a pair of left and right support brackets that support the swing fulcrum shaft of the lift arm are detachably attached to the upper part of the lateral transmission case portion, so that the rear axle case, which is a strength member, is supported. It can be used as a member to be attached to the bracket.
And since a pair of left and right support brackets are detachably attached to the upper part of the lateral transmission case, by removing the support brackets, another device can be mounted on the body frame of the specification that the lift arm can not be attached. It is easy to obtain a versatile passenger work machine that avoids getting in the way when placing it.

In the present invention, it is preferable that the pair of left and right support brackets are made of members having the same specifications.

According to this configuration, by configuring the left and right support brackets with members having the same specifications as each other, it is possible to use both parts and reduce the manufacturing cost.

In the present invention, the left and right lift arms are provided at positions equidistant from each other with respect to the center position of the pair of left and right main frames in the left-right direction.
The center position of the operating arm that swings the swing fulcrum axis of the left and right lift arms in the left-right direction, and the position of the center axis of the elevating cylinder that pushes and pulls the operating arm in the front-back direction are It is arranged so as to be biased to one direction in the left-right direction with respect to the center position.
The boss portion of the support bracket that pivotally supports the swing fulcrum axis is separated from the center position by different distances on the left and right, and the center position of the operating arm portion in the left-right direction, and the elevating cylinder. It is arranged equidistantly in the left-right direction with respect to the position of the central axis of.
Externally fitted to the swing fulcrum shaft between the operating arm portion and the left and right boss portions, and between the boss portion on the side closer to the center position and the lift arm located near the boss portion. It is preferable that a spacer is provided.

According to this configuration, the center position of the operating arm that swings the swing fulcrum axis of the lift arm in the left-right direction and the position of the center axis of the elevating cylinder that pushes and pulls the operating arm in the front-back direction. , Easy to set in a relatively free position. Therefore, the operating arm and the elevating cylinder can be used without any problem even if the operating arm and the elevating cylinder are arranged in the left-right direction with respect to the center position in the left-right direction of the main frame, and there is design freedom regarding the arrangement of the operating arm and the elevating cylinder. The degree can be increased.

In the present invention, one of the left and right lift arms and the lower link located on the same side in the left-right direction as the lift arm are connected by a rod-shaped first suspending member.
The lower link located on the same side as the other lift arm in the left-right direction and the other lift arm are connected by a second suspension member provided with a telescopic cylinder.
A Monroe valve that supplies and discharges pressure oil to the telescopic cylinder and a lifting valve that supplies and discharges pressure oil to the lifting cylinder of the lift arm are built in a common valve case.
The valve case is arranged in front of the rear axle case and below the driver's seat arranged at the center of the vehicle body frame in the left-right direction so as to overlap the driver's seat in a plan view. It is preferable that it is done.

According to this configuration, the Monroe valve that supplies and discharges pressure oil to the telescopic cylinder and the lifting valve that supplies and discharges pressure oil to the lifting cylinder of the lift arm are built in a common valve case. Compared to a structure in which individual valves are built in separate valve cases, the valve case can be made smaller as a whole. Moreover, since the miniaturized valve case is placed using the empty space under the driver's seat, it is possible to prevent the placed valve case from protruding downward as the ground height is lowered, and the entire aircraft is compact. Easy to configure.

In the present invention, the valve case overlaps the position where the elevating cylinder is arranged in the front-rear direction, and the lift arm is connected to the second suspending member from a position where the elevating cylinder exists in the left-right direction. It is preferable that the cylinders are unevenly arranged on the side where the cylinders are present.

According to this configuration, the valve case is arranged on the side where the lift arm connected to the second suspension member is present rather than the position where the elevating cylinder is arranged in the front-rear direction and the elevating cylinder is present in the left-right direction. Since it is uneven, the piping distance from the valve case to the elevating cylinder and the telescopic cylinder can be set short, and it is easy to configure the hydraulic equipment-related structure more compactly.

It is a left side view which shows the whole of a passenger work machine. It is a top view which shows the whole of a passenger work machine. It is a top view which shows the vehicle body frame and the elevating mechanism. It is a side view of the partial cross section which shows the body frame, the rear axle case, and the elevating mechanism. It is a top view which shows the mounting state of the elevating mechanism with respect to the rear axle case. FIG. 5 is a vertical sectional view showing a cross section taken along line VI-VI in FIG. It is a rear view which shows the mounting state of the elevating mechanism with respect to the rear axle case.

Hereinafter, an example of the embodiment of the present invention will be described based on the description in the drawings.
Unless otherwise specified, the front-back direction and the left-right direction in the description of the present embodiment are described as follows. That is, in the passenger work machine to which the present invention is applied, the traveling direction on the forward side (see arrows F in FIGS. 1 and 2) is "forward" and the traveling direction on the reverse side (FIGS. 1 and 2) when the traveling machine is working. (See arrow B in FIG. 2) is "rear", the direction corresponding to the right side with respect to the forward-looking posture in the front-back direction (see arrow R in FIG. 2) is "right", and similarly the direction corresponding to the left side (see FIG. 2). (See arrow L) is "left".

[Basic configuration of passenger work machine]
As an example of the passenger working machine according to the present invention, FIGS. 1 to 3 show a boom sprayer with an operating cabin, that is, a passenger management machine.
The traveling machine 1 in this boom sprayer includes a vehicle body frame 10, a pair of left and right front wheels 1F and 1F supported by the front axle case 11F, and a pair of left and right rear wheels 1R and 1R supported by the rear axle case 11R. I have.
The vehicle body frame 10 includes a pair of left and right main frames 10A and 10A along the front-rear direction and a horizontal frame 10B connecting the left and right main frames 10A and 10A at a plurality of locations in the front-rear direction, and the main frames 10A and 10A are vehicle body frames. The front axle case 11F located below the front portion of the vehicle body frame 10 and the rear axle case 11R located below the rear portion of the vehicle body frame 10 are provided. Front wheels 1F and 1F are rotatably supported around the horizontal axis core at both left and right ends of the front axle case 11F, and rear wheels 1R and 1R are rotatably supported around the horizontal axis center at both left and right ends of the rear axle case 11R. To.

The left and right ends of each of the front axle case 11F and the rear axle case 11R extend downward. This downwardly extending portion can rotate around the vertical axis. As a result, the front wheels 1F and 1F and the rear wheels 1R and 1R are configured to be capable of four-wheel steering.
Of the front axle case 11F and the rear axle case 11R, the specific configuration of the rear axle case 11R will be described with reference to FIGS. 1 to 4 and 7. Since the front axle case 11F also has almost the same structure and the same shape as the rear axle case 11R, detailed description of the front axle case 11F will be omitted.

As shown in FIGS. 1 to 4 and 7, the rear axle case 11R includes a pair of left and right vertical transmission case portions 12 and 12 supporting the left and right rear wheels 1R and 1R at the bottom, and rear wheels 1R and 1R. A horizontal transmission case portion 13 for connecting the upper portions of the vertical transmission case portions 12 and 12 at a position higher than the axis x1 of the above is provided, and is formed in a portal shape in the front-rear direction. The front axle case 11F is also formed in a gate shape substantially similar to the rear axle case 11R when viewed in the front-rear direction.

On the vehicle body frame 10, a driving portion 3 is provided at the front portion, and a boarding portion 4 is provided behind the driving portion 3. The driving unit 3 includes an engine 31 as a power source in a state of being built in the engine bonnet 30. The boarding unit 4 includes a driving cabin 40 in which a maneuvering operation tool and the like are incorporated.
A boom unit 20 for liquid spraying of the liquid spraying device 2 (corresponding to the drug spraying device) is connected to the front end portion of the vehicle body frame 10.
A chemical storage tank 28 is provided on the vehicle body frame 10 behind the driving cabin 40. The chemical liquid storage tank 28 constitutes the liquid spraying device 2 together with the boom unit 20. The chemical storage tank 28 is adjacent to the rear of the operating cabin 40. The left and right sides of the chemical storage tank 28 extend to the left and right sides of the rear part of the operation cabin 40 to the position of the rear part of the door 40B of the operation cabin 40 in the side view of the machine body. Therefore, the chemical liquid storage tank 28 is formed in a U shape in a plan view and has a shape surrounding the rear portion of the operating cabin 40.

An elevating mechanism 5 for connecting the working device 6 so as to be able to elevate is attached to the rear end portion of the vehicle body frame 10.
In this embodiment, a medium-cultivation work machine for performing medium-cultivation work is exemplified as the work device 6, but the present invention is not limited to this, and other work devices such as a weeding device may be attached.

[Boarding section]
The boarding unit 4 is provided with a driving cabin 40.
The operation cabin 40 includes a roof portion 46 in which an air conditioner (not shown) is incorporated. In the cabin interior space covered by the roof portion 46, a steering operation tool including a front panel 42, a steering handle 43 for steering operation, and the like are incorporated.
A windshield 40A is provided on the front surface of the driving cabin 40, and a door 40B that can be opened and closed is provided on the left side portion of the driving cabin 40. Inside the driving cabin 40, a space inside the cabin where the driver can board is formed. A driver's seat 41 and a front panel 42 are provided in the cabin space. The driver's seat 41 is provided in the central portion of the traveling machine body 1 and is configured so that the driver can take a seat. The front panel 42 is provided in the central portion of the traveling machine body 1 and is located in front of the driver's seat 41 and behind the windshield 40A.

The front panel 42 is provided with a steering handle 43 and various operating tools such as a main shift lever (not shown). The steering handle 43 is provided on the front portion of the boarding section 4 and is configured to enable maneuvering operations of the front wheels 1F and 1F and the rear wheels 1R and 1R by artificial operation. The forward / backward movement switching operation and the traveling speed change operation of the traveling machine body 1 can be performed by, for example, the operation of the main shift lever or the like, and the boom unit 20 or the working device 6 can be operated by various operation tools provided on the front panel 42 or the like. It is possible.

A side step 44 is provided on the left side of the machine body with respect to the door 40B, and the boarding / alighting step 45 extends downward from the rear portion of the side step 44 on the lateral outer side of the machine body. In other words, the boarding / alighting step 45 is provided on the left lateral outer side of the side step 44 and extends downward. Although not described in detail, a slide mechanism is provided at the front portion of the door 40B in the driving cabin 40, and the door 40B is configured to be slidable in the front-rear direction. As a result, the door 40B is configured to be switchable between a closed state in which the left side surface of the cabin interior space is closed and an open state in which the left side surface of the cabin interior space is opened. That is, when the door 40B in the closed state shown in FIG. 1 slides forward, the door 40B is switched to the open state. Then, when the door 40B in the open state slides backward, the door 40B is switched to the original closed state shown in FIG. The driver can enter the cabin space by climbing the boarding / alighting step 45, standing behind the side step 44, and opening the door 40B (switching to the open state).

The vehicle body frame 10 is provided with a portal frame 10C that connects the left and right main frames 10A and 10A so as to straddle each other from above. The driver's seat 41 is attached to the vehicle body frame 10 via a seat support device (not shown) supported by the gate-shaped frame 10C, and is mounted in a state of being inserted into the driver's cabin 40.

[Liquid sprayer]
The boom unit 20 has a center boom 21 and a pair of left and right side booms 22L and 22R. The boom unit 20 is supported by the front end portion of the vehicle body frame 10 via the elevating link mechanism 19 and the rolling mechanism 18.
The elevating link mechanism 19 has a first hydraulic cylinder 23 facing up and down. The first hydraulic cylinder 23 is a single rod type cylinder in which the piston rod is located below the first hydraulic cylinder 23. The elevating link mechanism 19 is configured to be able to move up and down by the expansion and contraction operation of the first hydraulic cylinder 23.

The rolling mechanism 18 is supported by the free end portion of the elevating link mechanism 19, and the center boom 21 and the pair of side booms 22L and 22R are supported by the rolling mechanism 18. The longitudinal direction of the center boom 21 is arranged sideways to the machine body. The left and right side booms 22L and 22R are pivotally supported at both ends in the longitudinal direction of the center boom 21. Second hydraulic cylinders 24L and 24R are provided at the pivot points at both ends of the center boom 21 in the longitudinal direction.
Each of the second hydraulic cylinders 24L and 24R is connected over the longitudinal end of the center boom 21 and the left and right side booms 22L and 22R pivotally connected to the end, and these second hydraulic cylinders 24L are connected. The left and right side booms 22L and 22R can be swung by the expansion and contraction operation of 24R.

When the second hydraulic cylinder 24L is extended, the side boom 22L extends laterally to the same direction as the center boom 21. In this case, the side boom 22L extends laterally outward from the traveling machine body 1. When the second hydraulic cylinder 24L contracts, the side boom 22L is folded in a state of being inclined backward. Similar to the case of the side boom 22L, the side boom 22R extends laterally when the second hydraulic cylinder 24R extends. Further, when the second hydraulic cylinder 24R contracts, the side boom 22R is folded in a state of being inclined backward. The side booms 22L and 22R are tilted backward, and the free ends of the side booms 22L and 22R are located at locations corresponding to the rear ends of the traveling machine 1 in the front-rear direction, and the operation cabin 40 is located in the vertical direction. It is located below the upper end of.

Each of the center boom 21 and the pair of side booms 22L and 22R is provided with a drug supply pipe 25 along the longitudinal direction, and the drug supply pipe 25 is provided with a large number of spray nozzles 26. Further, a spraying pump 27 (see FIG. 1 and the like) is supported below the driver's seat 41 in the vehicle body frame 10. The spraying pump 27 is configured to be able to discharge the liquid drug stored in the drug solution storage tank 28 toward the drug supply pipe 25.

When spraying the chemicals, the driver extends the pair of left and right side booms 22L and 22R sideways to drive the spraying pump 27 based on the power of the engine 31. As a result, the liquid medicine stored in the medicine liquid storage tank 28 is sprayed from a large number of spray nozzles 26 through the medicine supply pipe 25. The spraying pump 27 is configured to be capable of spraying and driving the boom unit 20 as the liquid spraying device 2. In this state, the traveling machine 1 travels in the field by the rotational drive of the front wheels 1F, 1F and the rear wheels 1R, 1R, and the chemicals are sprayed on the field.

Further, when the chemical is not sprayed, the driver folds the pair of left and right side booms 22L and 22R in the rearward upward direction. As a result, when the boom sprayer runs on a farm road or is parked in a barn for storage, the possibility that the free end portions of the side booms 22L and 22R come into contact with other objects is reduced.

[Elevating mechanism]
The elevating mechanism 5 for elevating and lowering the working device 6 is configured as follows.
As shown in FIGS. 3 to 7, the elevating mechanism 5 includes a link mechanism 5A for connecting the vehicle body frame 10 and the working device 6, and an elevating device 5B for raising and lowering the link mechanism 5A.

[Link mechanism]
The link mechanism 5A is a pair of left and right lower links 53 composed of a rod-shaped top link 51 configured to be adjustable in length and a plate-shaped long member having a vertical width wider than the lateral width. , 53, and.
The base end portion of the top link 51 is a horizontal axis along the horizontal direction with respect to the top link mounting portion 50 provided on the upper fulcrum bracket 14 fixed to the upper surface of the horizontal frame 10B connecting the rear portions of the left and right main frames 10A. It is connected so that it can swing up and down around the center p1.
The base end portion of the lower link 53 is located behind the lateral transmission case portion 13 with respect to the lower link mounting portion 52 provided at the lower portion of the lower fulcrum bracket 15 extending downward from the left and right main frames 10A. Therefore, they are connected so as to be vertically swingable around the horizontal axis p2 along the horizontal direction.

As shown in FIGS. 3 and 7, the lower link mounting portion 52 is set at a height corresponding to the minimum ground clearance h1 and at a height similar to that of the lower edge 13a of the lateral transmission case portion 13. Has been done. As shown in the enlarged view of FIG. 7, the support member 61 of the PTO shaft 60 is detachably bolted to a part of the outer peripheral portion of the lateral transmission case portion 13 at a height position corresponding to the lower edge 13a. Has been done.
Since the PTO shaft 60 and the support member 61 are connected in a state of being lower than the lower edge 13a of the lateral transmission case portion 13, in a state where the PTO shaft 60 and the support member 61 are attached, the PTO shaft 60 and the support member 61 are laterally oriented. The height of the lower edge 13a of the transmission case portion 13 is not the minimum ground clearance of the passenger work machine, but is the height corresponding to the minimum ground clearance h1 with the PTO shaft 60 and the support member 61 removed. Become. That is, the height of the lower edge 13a of the lateral transmission case portion 13, which is a non-detachable member such as the PTO shaft 60 and the support member 61, corresponds to the minimum ground clearance h1 in the present invention.

In this embodiment, as shown in FIG. 7, a bulging portion 13b that slightly protrudes downward from the lower edge 13a of the lateral transmission case portion 13 is provided, and the connecting bolt 61a of the support member 61 is provided here. A screw hole (not shown) is formed. Therefore, strictly speaking, there is a bulging portion 13b lower than the minimum ground clearance h1.
However, in a passenger working machine having specifications that do not use the PTO shaft 60 or the support member 61, it is not necessary to have the above-mentioned bulging portion 13b. Further, even when the bulging portion 13b is provided, the bulging amount is small, the existence range is also very small, and the bulging portion 13b is negligible. Therefore, in the present invention, such a bulging portion 13b is provided. The height of the lower edge 13a of the lateral transmission case portion 13 is defined as the height corresponding to the minimum ground clearance h1 regardless of the presence or absence of the above.

As shown in FIGS. 5 to 7, the lower fulcrum bracket 15 is welded and fixed to the lower surface side of the main frame 10A, and extends downward from the main frame 10A. As shown in FIG. 5, in a plan view, the rear side is formed in an open channel shape, and is detachably connected to the rear surface of the lateral transmission case portion 13 with a connecting bolt 15a.
On the front surface of the lateral transmission case portion 13, a front bracket 16 which is welded and fixed to the lower surface side of the main frame 10A and extends downward from the main frame 10A is provided. The front bracket 16 is formed in a channel shape with an open front, and is connected to the front surface of the lateral transmission case portion 13 by a connecting bolt 16a. Although not shown, a power steering device (not shown) for steering the rear wheels 1R and 1R is supported in the lower portion of the front bracket 16.

〔lift device〕
The elevating device 5B is a suspending member that connects a pair of left and right lift arms 54 for raising and lowering the lower link 53 and an end portion of each lift arm 54 on the free end side to an intermediate portion in the length direction of the left and right lower link 53. It is provided with 55 and a lifting cylinder 56 for swinging the lift arm 54 around a swing axis x2 along a horizontal direction.
The elevating cylinder 56 is arranged with its central axis CL2 along the front-rear direction of the traveling machine body 1, and is pushed and pulled in the front-rear direction as pressure oil is supplied and discharged from the elevating valve 63, which will be described later. It is configured in.

In the lift arm 54, the elevating arm portions 54L and 54R extending toward the rear side are integrally connected to the left-right end portion of the swing fulcrum shaft 54a provided with the swing shaft center x2. An operating arm portion 54C is integrally connected to the central portion of the swing fulcrum shaft 54a in the left-right direction toward the front and lower directions.
The front end portion of the operating arm portion 54C is connected to the rear end portion of the elevating cylinder 56 whose front end portion is connected to the lateral frame 10B of the vehicle body frame 10. Therefore, the operating arm portion 54C is rotated as the elevating cylinder 56 expands and contracts. Along with this, the elevating arm portions 54L and 54R provided at the left and right ends of the swing fulcrum shaft 54a also rotate around the swing axis x2, and the lower link 53 connected via the suspension member 55 is lateral. It swings around the axis p2.

The suspending member 55 includes a first suspending member 55R and a second suspending member 55L.
The first suspending member 55R connects the right elevating arm portion 54R and the right lower link 53 of the elevating arm portions 54L and 54R.
The second suspending member 55L connects the left lifting arm portion 54L and the left lower link 53 of the lifting arm portions 54L and 54R.
As shown in FIGS. 5 and 6, the first suspension member 55R is composed of a rod-shaped rod member, and the second suspension member 55L has an extension / contraction for length adjustment in an intermediate portion as shown in FIGS. 4 and 5. A cylinder 57 is interposed. The telescopic cylinder 57 is expanded and contracted by the action of supplying and discharging the pressure oil from the Monroe valve 64, which will be described later, so that the working device 6 is connected to the traveling machine body 1 so as to be relatively rolling. Has been done.

As shown in FIGS. 5 to 7, the swing fulcrum shaft 54a is pivotally supported by a pair of left and right support brackets 58, and is rotatably supported around the swing shaft center x2. The support bracket 58 that pivotally supports the swing fulcrum shaft 54a is detachably attached to the upper portion of the lateral transmission case portion 13 in the rear axle case 11R.
At the upper part of the lateral transmission case portion 13, a horizontal seat portion 13c whose mounting surface is along the horizontal direction and a vertical seat portion 13d whose mounting surface is vertically aligned behind the horizontal seat portion 13c are provided. (See Fig. 6). The horizontal seat portion 13c and the vertical seat portion 13d are formed so that the extension lines of the mounting surfaces are substantially orthogonal to each other. Further, at the lower part of the support bracket 58, a mounting surface is provided which faces and abuts the mounting surface of the horizontal seat portion 13c and the vertical seat portion 13d. That is, the mounting surface formed on the lower portion of the support bracket 58 is an extension of the mounting surface so as to have the same shape as the mounting surface of the horizontal seat portion 13c and the vertical seat portion 13d provided in the lateral transmission case portion 13. They are almost orthogonal to each other.
A boss portion 58a for pivotally supporting the swing fulcrum shaft 54a is provided on the upper portion of the support bracket 58.

As shown in FIGS. 5 to 7, the left and right support brackets 58 and 58 have the same specifications as each other. By using the same specifications in this way, the number of parts can be reduced.
As shown in FIGS. 5 and 7, the support brackets 58 and 58 and the elevating cylinder 56 are centered on the elevating cylinder 56 with respect to the machine center line CL1 indicating the center position of the traveling machine 1 in the left-right direction. The axis CL2 is arranged so as to be slightly offset to the right. However, the left and right lift arms 54, 54 and the left and right main frames 10A, 10A are arranged so that the distances from the aircraft center line CL1 in the left-right direction are equidistant on the left and right.
As a result, of the left and right support brackets 58 and 58, the left support bracket 58 is separated from the left lift arm 54 toward the aircraft center line CL1 and closer to the aircraft center line CL1 than the right support bracket 58. It is placed in a position.
The right support bracket 58 swings at a position where the end surface of the boss portion 58a on the outside side of the machine abuts on the end surface of the right lift arm 54 connected to the right end of the swing fulcrum shaft 54a. It supports the fulcrum shaft 54a.

The separation distance between the left and right support brackets 58, 58 is formed to be larger than the width in the left-right direction of the operating arm portion 54C fixed to the intermediate portion in the left-right direction of the swing fulcrum shaft 54a. Therefore, there is a gap between the left and right support brackets 58 and 58 and the operating arm portion 54C. Further, the swing fulcrum shaft 54a is connected to the lift arm 54 on the left side at a position extending laterally outward from the support bracket 58 on the left side.
Therefore, there is a swing fulcrum between the boss portions 58a and 58a of the left and right support brackets 58 and 58 and the operating arm portion 54C, and between the boss portion 58a of the left support bracket 58 and the left lift arm 54. The spacer 59 is provided so as to be fitted on the shaft 54a.
The spacer 59 includes a pair of left and right first spacers 59a, 59a having a length corresponding to the distance between the boss portions 58a, 58a of the left and right support brackets 58, 58 and the operating arm portion 54C, and the left support. It is provided with a second spacer 59b that is externally fitted to the swing fulcrum shaft 54a located between the bracket 58 and the lift arm 54 on the left side. The first spacers 59a and 59a are formed to have the same left-right length as each other, and the second spacer 59b is formed to have a slightly shorter left-right length than the first spacer 59a.

[Valve case]
As shown in FIG. 3, a valve case 62 is arranged below the driver's seat 41 arranged at the center of the vehicle body frame 10 in the left-right direction so as to overlap the driver's seat 41 in a plan view.
The valve case 62 includes a lifting valve 63 that supplies and discharges pressure oil to the lifting cylinder 56 of the lift arm 54, and a monroe valve 64 that supplies and discharges pressure oil to the telescopic cylinder 57 provided in the second suspension member 55L. And are built into a common valve block. The valve case 62 referred to here includes not only the elevating valve 63 and the monroe valve 64, but also a member for attaching the elevating valve 63 and the monroe valve 64 to the vehicle body frame 10.

The valve case 62 has a lift arm 54 on the left side connected to the second suspension member 55L from the position where the elevating cylinder 56 is arranged in the front-rear direction and overlaps with the elevating cylinder 56 in the left-right direction. It is arranged unevenly on the side of the cylinder.
Then, the pressure oil supply pipe 63a extends toward the elevating cylinder 56 from the elevating valve 63 located near the elevating cylinder 56 in the left-right direction. Between the Monroe valve 64 located closer to the telescopic cylinder 57 in the left-right direction and the telescopic cylinder 57, a pressure oil supply / discharge pipe 64a extends between the lift arm 54 on the left side and the main frame 10A on the left side. There is.

[Another Embodiment]
Hereinafter, another embodiment will be described. Each of the following separate embodiments may be applied to the above embodiment in combination as long as there is no contradiction. The scope of the present invention is not limited to the contents of these embodiments.

(1) In the above-described embodiment, as the link mechanism 5A, a structure in which the top link 51 is composed of a single rod-shaped member and has a three-point link type structure is exemplified, but the structure is not necessarily limited to this structure. It's not a thing.
For example, the top link 51 may be appropriately modified and used, for example, the top link 51 is composed of a plurality of plate-shaped members.
For other configurations, the same configurations as those in the above-described embodiment may be adopted.

(2) In the above-described embodiment, the first suspension member 55R is composed of a rod-shaped rod member as the suspension member 55 connecting the pair of left and right lift arms 54 and the pair of left and right lower links 53, and the second. The suspension member 55L has an example of a structure in which a telescopic cylinder 57 for adjusting the length is interposed in the middle portion, but the suspension member 55L is not necessarily limited to this structure.
For example, the first suspension member 55R and the second suspension member 55L are both composed of a rod-shaped rod member, or the first suspension member 55R and the second suspension member 55L are both intermediate. It may have a structure in which a telescopic cylinder 57 for adjusting the length is interposed in the portion.
For other configurations, the same configurations as those in the above-described embodiment may be adopted.

(3) In the above-described embodiment, the lower link mounting portion 52 for supporting the base end portion of the lower link 53 is provided on the lower fulcrum bracket 15 formed in a channel shape with the rear side open in a plan view. Although the lower fulcrum bracket 15 has a structure configured to be connectable to the rear surface of the lateral transmission case portion 13, the structure is not necessarily limited to this.
For example, the lower fulcrum bracket 15 is composed of a rectangular tubular member or the like, and is not connected to the rear surface of the lateral transmission case portion 13, but simply extends downward from the main frame 10A. There is no problem.
It is connected as possible.

(4) In the above-described embodiment, the lower link mounting portion 52 is an outer peripheral portion of the lateral transmission case portion 13 and has a structure provided at a height corresponding to the lower edge 13a. Not limited to those that exactly match the lower edge 13a of the outer peripheral portion of the portion 13, the position is somewhat lower than the lower edge 13a of the outer peripheral portion of the lateral transmission case portion 13, or the lower edge of the outer peripheral portion of the lateral transmission case portion 13. It may be provided at a position higher than 13a to some extent.
For other configurations, the same configurations as those in the above-described embodiment may be adopted.

(5) In the above-described embodiment, there is an example in which the center axis CL2 of the elevating cylinder 56 is slightly biased to the right with respect to the machine center line CL1 indicating the center position of the traveling machine 1 in the left-right direction. However, it is not necessarily limited to this structure.
For example, the center axis CL2 of the elevating cylinder 56 may be slightly biased to the left with respect to the machine center line CL1, or the body center line CL1 and the center axis CL2 of the elevating cylinder 56 may coincide with each other. , May be.
For other configurations, the same configurations as those in the above-described embodiment may be adopted.

The present invention is not limited to a passenger working machine equipped with a liquid spraying device, but can be applied to various riding working machines equipped with a working device capable of working on agricultural products in a field.

1 Traveling machine 1F Front wheel 1R Rear wheel 10 Body frame 10A Main frame 10B Horizontal frame 11F Front axle case 11R Rear axle case 12 Vertical transmission case 13 Horizontal transmission case 14 Upper fulcrum bracket 15 Lower fulcrum bracket 41 Driver's seat 50 Top link Mounting part 51 Top link 52 Lower link mounting part 53 Lower link 54 Lift arm 54a Swing fulcrum shaft CL1 Central position 54C Operating arm 55L Second hanging member 55R First hanging member 56 Lifting cylinder CL2 Center axis 57 Telescopic cylinder 58 Support bracket 58a Boss 59 Spacer 62 Valve case 63 Lifting valve 64 Monroe valve

Claims (7)

A front axle case with a power transmission mechanism that transmits power to a pair of left and right front wheels,
A rear axle case with a power transmission mechanism that transmits power to a pair of left and right rear wheels,
A vehicle body frame supported by the front axle case and the rear axle case is provided.
The engine and transmission case are supported by the body frame,
The vehicle body frame includes a pair of left and right main frames erected over the front axle case and the rear axle case.
The rear axle case connects the pair of left and right vertical transmission case portions that support the left and right rear wheels to the lower portion and the upper portions of the vertical transmission case portions at a position higher than the axis of the rear wheels. With a sideways transmission case, it is formed in a portal shape in the front-back direction.
A lateral frame connecting the rear portions of the main frame to the rear of the vehicle body frame on the rear side of the lateral transmission case portion, and a lateral frame extending downward from the main frame at a rear portion of the lateral transmission case portion. With a lower fulcrum bracket,
A top link mounting portion capable of connecting the top link is provided on the horizontal frame.
A lower link mounting portion to which a lower link can be connected is provided at the lower end of the lower fulcrum bracket.
The lower link mounting portion is a passenger work machine set at a height similar to that of the lower edge of the lateral transmission case portion. The passenger working machine according to claim 1, wherein the lower fulcrum bracket is connected to the rear surface of the lateral transmission case portion in contact with the rear surface. A lift arm for raising and lowering the lower link connected to the lower link mounting portion is provided.
A swing fulcrum axis along the left-right direction of the lift arm is pivotally supported by a pair of left and right support brackets.
The passenger working machine according to claim 1 or 2, wherein the support bracket is detachably attached to the upper part of the lateral transmission case portion. The passenger working machine according to claim 3, wherein the pair of left and right support brackets are made of members having the same specifications as each other. The left and right lift arms are provided at positions equidistant from each other with respect to the center position of the pair of left and right main frames in the left-right direction.
The center position of the operating arm that swings the swing fulcrum axis of the left and right lift arms in the left-right direction, and the position of the center axis of the elevating cylinder that pushes and pulls the operating arm in the front-back direction are It is arranged so as to be biased to one direction in the left-right direction with respect to the center position.
The boss portion of the support bracket that pivotally supports the swing fulcrum axis is separated from the center position by different distances on the left and right, and the center position of the operating arm portion in the left-right direction, and the elevating cylinder. It is arranged equidistantly in the left-right direction with respect to the position of the central axis of.
Externally fitted to the swing fulcrum shaft between the operating arm portion and the left and right boss portions, and between the boss portion on the side closer to the center position and the lift arm located near the boss portion. The passenger working machine according to claim 4, which is provided with a spacer. Of the left and right lift arms, one of the lift arms and the lower link located on the same side in the left-right direction from the lift arm are connected by a rod-shaped first suspending member.
The lower link located on the same side as the other lift arm in the left-right direction and the other lift arm are connected by a second suspension member provided with a telescopic cylinder.
A Monroe valve that supplies and discharges pressure oil to the telescopic cylinder and a lifting valve that supplies and discharges pressure oil to the lifting cylinder of the lift arm are built in a common valve case.
The valve case is arranged in front of the rear axle case and below the driver's seat arranged at the center of the vehicle body frame in the left-right direction so as to overlap the driver's seat in a plan view. The passenger working machine according to any one of claims 3 to 5. The valve case overlaps the position where the elevating cylinder is arranged in the front-rear direction, and the side where the lift arm connected to the second suspension member exists rather than the position where the elevating cylinder exists in the left-right direction. The passenger working machine according to claim 6, which is unevenly arranged in the vehicle.

Images